Rock bolts are commonly used in tunnelling or mining to support a rock face and/or to provide an anchorage point adjacent the rock face within the tunnel or mine. Rock bolts comprise elongated bolts which are fitted into holes drilled into a rock face. The rock bolt may be several metres long, the length depending upon the type and condition of the rock. Rock bolts are typically used to support the rock above a ceiling of a tunnel or chamber, but may alternatively be used to support the rock behind a wall thereof.